Genome sequencing time can be reduced to minutes

Scientists from Imperial College London have patented technology which could unravel the human genome in minutes.

Current tools which sequence DNA are incredibly complex, time-consuming and expensive but new research suggests that, within ten years, the entire human genome could be sequenced in minutes and at a fraction of the cost.

The new technique could, according to the researchers, allow ordinary people to unlock the secrets of their own DNA, revealing their personal susceptibility to diseases such as Alzheimer's, diabetes and cancer.

The medical world is already using genome sequencing to understand global health issues and to find preventions and cures for some of the world's biggest killers.

Dr Joshua Edel, one of the authors on the study from the Department of Chemistry at Imperial College London, said: "Compared with current technology, this device could lead to much cheaper sequencing: just a few dollars, compared with $1 million to sequence an entire genome in 2007.

"We haven't tried it on a whole genome yet but our initial experiments suggest that you could theoretically do a complete scan of the 3,165 million bases in the human genome within minutes, providing huge benefits for medical tests, or DNA profiles for police and security work. It should be significantly faster and more reliable, and would be easy to scale up to create a device with the capacity to read up to 10 million bases per second, versus the typical 10 bases per second you get with the present day single molecule real-time techniques."

The new technique involves blasting a single DNA strand through a tiny 50 nanometre hole drilled in a silicon chip and reading the sequence bases (A, C, T or G) using a 'tunneling electrode junction' on the other side.

Basically, it's two tiny wires two nanometres apart which can detect the distinct electrical signals created by the four bases and send those signals to a powerful computer for interpretation.

All of the technique haves been around theoretically for some time but this is the first time they have been combined into a fast and accurate reader according to the research.

Co-author Dr Emanuele Instuli said, "Getting the DNA strand through the nanopore is a bit like sucking up spaghetti. Until now it has been difficult to precisely align the junction and the nanopore. Furthermore, engineering the electrode wires with such dimensions approaches the atomic scale and is effectively at the limit of existing instrumentation.

"However in this experiment we were able to make two tiny platinum wires into an electrode junction with a gap sufficiently small to allow the electron current to flow between them."

Current techniques involve using chemical processes to break DNA strands into smaller chunks before sequencing and use delicate materials which degrade over time. The silicon chips involved in the new technique can be used again and again.

Give it twenty years and we reckon you'll be able to pop into your local chemist and have your DNA sequenced along with checking your blood pressure, cholesterol and body mass index.